Because people like Adam Maysonet were playing all Moxes and Balances and Armageddons, and killing people with Dingus Egg damage
For example, if you dont have a second land, you want to discard something from hand, or the opponent has a graveyard hate ready
Yes, continuous shuffling of the decks prevents card counting, shuffle tracking and advantaged players
As far as the combo itself, it's worth mentioning that Putrid Goblin needs to not have a 1/1 counter on it when we start the combo, which means we often don't want to chump block with it unless we have Thran Vigil on the battlefield or if we are desperate
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